1. Field of the Invention
The present invention relates to an engine driven type of working machine, which stops its operation while standby state to eliminate wasteful running.
2. Description of the Related Art
An engine driven type of high-pressure washing machine which can discharge washing water with an engine driven pump is well known. For example, Japanese Patent Publication of examined patent application No. H5-38132 and Japanese patent Publication of examined Utility Model application No. H6-41673 disclose a control device in the engine driven type of high-pressure washing machine which can automatically decrease engine revolution speed while stopping wash operation. The control device saves fuel, reduces exhaust gas, and decreases running noise.
In the control device described in the above Patent Publications, because the engine is operated at the low number of revolutions while being in a standby state, the fuel economy can be improved to a certain level, however it is not sufficient. The high-pressure pump is still running even while the washing operation is pausing, so power supply is needed to return excess water or unloaded water back to a water tank, that causes waste of energy.
In order to improve effects such as a fuel economy, it is thought stopping the engine during a pause in the washing operation. However, an operator is forced to operate to turn off a switch provided for start and stop washing and to perform stop operation of the engine besides. Therefore, it is desired to save energy efficiently and to save operator's needless operation.